test/tck/SynchronousQueueTest.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/licenses/publicdomain
 * Other contributors include Andrew Wright, Jeffrey Hayes,
 * Pat Fisher, Mike Judd.
 */

import junit.framework.*;
import java.util.*;
import java.util.concurrent.*;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import java.io.*;

public class SynchronousQueueTest extends JSR166TestCase {

    public static class Fair extends BlockingQueueTest {
        protected BlockingQueue emptyCollection() {
            return new SynchronousQueue(true);
        }
    }

    public static class NonFair extends BlockingQueueTest {
        protected BlockingQueue emptyCollection() {
            return new SynchronousQueue(false);
        }
    }

    public static void main(String[] args) {
        junit.textui.TestRunner.run(suite());
    }

    public static Test suite() {
        return newTestSuite(SynchronousQueueTest.class,
                            new Fair().testSuite(),
                            new NonFair().testSuite());
    }

    /**
     * A SynchronousQueue is both empty and full
     */
    public void testEmptyFull() {
        SynchronousQueue q = new SynchronousQueue();
        assertTrue(q.isEmpty());
        assertEquals(0, q.size());
        assertEquals(0, q.remainingCapacity());
        assertFalse(q.offer(zero));
    }

    /**
     * A fair SynchronousQueue is both empty and full
     */
    public void testFairEmptyFull() {
        SynchronousQueue q = new SynchronousQueue(true);
        assertTrue(q.isEmpty());
        assertEquals(0, q.size());
        assertEquals(0, q.remainingCapacity());
        assertFalse(q.offer(zero));
    }

    /**
     * offer(null) throws NPE
     */
    public void testOfferNull() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            q.offer(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * add(null) throws NPE
     */
    public void testAddNull() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            q.add(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * offer fails if no active taker
     */
    public void testOffer() {
        SynchronousQueue q = new SynchronousQueue();
        assertFalse(q.offer(one));
    }

    /**
     * add throws ISE if no active taker
     */
    public void testAdd() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            assertEquals(0, q.remainingCapacity());
            q.add(one);
            shouldThrow();
        } catch (IllegalStateException success) {}
    }

    /**
     * addAll(null) throws NPE
     */
    public void testAddAll1() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            q.addAll(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * addAll(this) throws IAE
     */
    public void testAddAllSelf() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            q.addAll(q);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * addAll of a collection with null elements throws NPE
     */
    public void testAddAll2() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            Integer[] ints = new Integer[1];
            q.addAll(Arrays.asList(ints));
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * addAll throws ISE if no active taker
     */
    public void testAddAll4() {
        try {
            SynchronousQueue q = new SynchronousQueue();
            Integer[] ints = new Integer[1];
            for (int i = 0; i < 1; ++i)
                ints[i] = new Integer(i);
            q.addAll(Arrays.asList(ints));
            shouldThrow();
        } catch (IllegalStateException success) {}
    }

    /**
     * put(null) throws NPE
     */
    public void testPutNull() throws InterruptedException {
        try {
            SynchronousQueue q = new SynchronousQueue();
            q.put(null);
            shouldThrow();
        } catch (NullPointerException success) {}
     }

    /**
     * put blocks interruptibly if no active taker
     */
    public void testBlockingPut() throws InterruptedException {
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                SynchronousQueue q = new SynchronousQueue();
                q.put(zero);
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * put blocks waiting for take
     */
    public void testPutWithTake() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue();
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                int added = 0;
                try {
                    while (true) {
                        q.put(added);
                        ++added;
                    }
                } catch (InterruptedException success) {
                    assertEquals(1, added);
                }
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        assertEquals(0, q.take());
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * timed offer times out if elements not taken
     */
    public void testTimedOffer() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue();
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                assertFalse(q.offer(new Object(), SHORT_DELAY_MS, MILLISECONDS));
                q.offer(new Object(), LONG_DELAY_MS, MILLISECONDS);
            }});

        t.start();
        Thread.sleep(SMALL_DELAY_MS);
        t.interrupt();
        t.join();
    }


    /**
     * take blocks interruptibly when empty
     */
    public void testTakeFromEmpty() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue();
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                q.take();
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }


    /**
     * put blocks interruptibly if no active taker
     */
    public void testFairBlockingPut() throws InterruptedException {
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                SynchronousQueue q = new SynchronousQueue(true);
                q.put(zero);
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * put blocks waiting for take
     */
    public void testFairPutWithTake() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue(true);
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                int added = 0;
                try {
                    while (true) {
                        q.put(added);
                        ++added;
                    }
                } catch (InterruptedException success) {
                    assertEquals(1, added);
                }
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        assertEquals(0, q.take());
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * timed offer times out if elements not taken
     */
    public void testFairTimedOffer() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue(true);
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                assertFalse(q.offer(new Object(), SHORT_DELAY_MS, MILLISECONDS));
                q.offer(new Object(), LONG_DELAY_MS, MILLISECONDS);
            }});

        t.start();
        Thread.sleep(SMALL_DELAY_MS);
        t.interrupt();
        t.join();
    }


    /**
     * take blocks interruptibly when empty
     */
    public void testFairTakeFromEmpty() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue(true);
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                q.take();
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * poll fails unless active taker
     */
    public void testPoll() {
        SynchronousQueue q = new SynchronousQueue();
        assertNull(q.poll());
    }

    /**
     * timed pool with zero timeout times out if no active taker
     */
    public void testTimedPoll0() throws InterruptedException {
        SynchronousQueue q = new SynchronousQueue();
        assertNull(q.poll(0, MILLISECONDS));
    }

    /**
     * timed pool with nonzero timeout times out if no active taker
     */
    public void testTimedPoll() throws InterruptedException {
        SynchronousQueue q = new SynchronousQueue();
        assertNull(q.poll(SHORT_DELAY_MS, MILLISECONDS));
    }

    /**
     * Interrupted timed poll throws InterruptedException instead of
     * returning timeout status
     */
    public void testInterruptedTimedPoll() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue();
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                q.poll(SMALL_DELAY_MS, MILLISECONDS);
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * Interrupted timed poll throws InterruptedException instead of
     * returning timeout status
     */
    public void testFairInterruptedTimedPoll() throws InterruptedException {
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                SynchronousQueue q = new SynchronousQueue(true);
                q.poll(SMALL_DELAY_MS, MILLISECONDS);
            }});

        t.start();
        Thread.sleep(SHORT_DELAY_MS);
        t.interrupt();
        t.join();
    }

    /**
     * timed poll before a delayed offer fails; after offer succeeds;
     * on interruption throws
     */
    public void testFairTimedPollWithOffer() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue(true);
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                try {
                    assertNull(q.poll(SHORT_DELAY_MS, MILLISECONDS));
                    assertSame(zero, q.poll(LONG_DELAY_MS, MILLISECONDS));
                    q.poll(LONG_DELAY_MS, MILLISECONDS);
                    threadShouldThrow();
                } catch (InterruptedException success) {}
            }});

        t.start();
        Thread.sleep(SMALL_DELAY_MS);
        assertTrue(q.offer(zero, SHORT_DELAY_MS, MILLISECONDS));
        t.interrupt();
        t.join();
    }


    /**
     * peek returns null
     */
    public void testPeek() {
        SynchronousQueue q = new SynchronousQueue();
        assertNull(q.peek());
    }

    /**
     * element throws NSEE
     */
    public void testElement() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            q.element();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * remove throws NSEE if no active taker
     */
    public void testRemove() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            q.remove();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * remove(x) returns false
     */
    public void testRemoveElement() {
        SynchronousQueue q = new SynchronousQueue();
        assertFalse(q.remove(zero));
        assertTrue(q.isEmpty());
    }

    /**
     * contains returns false
     */
    public void testContains() {
        SynchronousQueue q = new SynchronousQueue();
        assertFalse(q.contains(zero));
    }

    /**
     * clear ensures isEmpty
     */
    public void testClear() {
        SynchronousQueue q = new SynchronousQueue();
        q.clear();
        assertTrue(q.isEmpty());
    }

    /**
     * containsAll returns false unless empty
     */
    public void testContainsAll() {
        SynchronousQueue q = new SynchronousQueue();
        Integer[] empty = new Integer[0];
        assertTrue(q.containsAll(Arrays.asList(empty)));
        Integer[] ints = new Integer[1]; ints[0] = zero;
        assertFalse(q.containsAll(Arrays.asList(ints)));
    }

    /**
     * retainAll returns false
     */
    public void testRetainAll() {
        SynchronousQueue q = new SynchronousQueue();
        Integer[] empty = new Integer[0];
        assertFalse(q.retainAll(Arrays.asList(empty)));
        Integer[] ints = new Integer[1]; ints[0] = zero;
        assertFalse(q.retainAll(Arrays.asList(ints)));
    }

    /**
     * removeAll returns false
     */
    public void testRemoveAll() {
        SynchronousQueue q = new SynchronousQueue();
        Integer[] empty = new Integer[0];
        assertFalse(q.removeAll(Arrays.asList(empty)));
        Integer[] ints = new Integer[1]; ints[0] = zero;
        assertFalse(q.containsAll(Arrays.asList(ints)));
    }


    /**
     * toArray is empty
     */
    public void testToArray() {
        SynchronousQueue q = new SynchronousQueue();
        Object[] o = q.toArray();
        assertEquals(o.length, 0);
    }

    /**
     * toArray(a) is nulled at position 0
     */
    public void testToArray2() {
        SynchronousQueue q = new SynchronousQueue();
        Integer[] ints = new Integer[1];
        assertNull(ints[0]);
    }

    /**
     * toArray(null) throws NPE
     */
    public void testToArray_BadArg() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            Object o[] = q.toArray(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }


    /**
     * iterator does not traverse any elements
     */
    public void testIterator() {
        SynchronousQueue q = new SynchronousQueue();
        Iterator it = q.iterator();
        assertFalse(it.hasNext());
        try {
            Object x = it.next();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * iterator remove throws ISE
     */
    public void testIteratorRemove() {
        SynchronousQueue q = new SynchronousQueue();
        Iterator it = q.iterator();
        try {
            it.remove();
            shouldThrow();
        } catch (IllegalStateException success) {}
    }

    /**
     * toString returns a non-null string
     */
    public void testToString() {
        SynchronousQueue q = new SynchronousQueue();
        String s = q.toString();
        assertNotNull(s);
    }


    /**
     * offer transfers elements across Executor tasks
     */
    public void testOfferInExecutor() {
        final SynchronousQueue q = new SynchronousQueue();
        ExecutorService executor = Executors.newFixedThreadPool(2);

        executor.execute(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                assertFalse(q.offer(one));
                assertTrue(q.offer(one, MEDIUM_DELAY_MS, MILLISECONDS));
                assertEquals(0, q.remainingCapacity());
            }});

        executor.execute(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                Thread.sleep(SMALL_DELAY_MS);
                assertSame(one, q.take());
            }});

        joinPool(executor);
    }

    /**
     * poll retrieves elements across Executor threads
     */
    public void testPollInExecutor() {
        final SynchronousQueue q = new SynchronousQueue();
        ExecutorService executor = Executors.newFixedThreadPool(2);
        executor.execute(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                assertNull(q.poll());
                assertSame(one, q.poll(MEDIUM_DELAY_MS, MILLISECONDS));
                assertTrue(q.isEmpty());
            }});

        executor.execute(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                Thread.sleep(SHORT_DELAY_MS);
                q.put(one);
            }});

        joinPool(executor);
    }

    /**
     * a deserialized serialized queue is usable
     */
    public void testSerialization() throws Exception {
        SynchronousQueue q = new SynchronousQueue();
        ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
        ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
        out.writeObject(q);
        out.close();

        ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
        ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
        SynchronousQueue r = (SynchronousQueue)in.readObject();
        assertEquals(q.size(), r.size());
        while (!q.isEmpty())
            assertEquals(q.remove(), r.remove());
    }

    /**
     * drainTo(null) throws NPE
     */
    public void testDrainToNull() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            q.drainTo(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * drainTo(this) throws IAE
     */
    public void testDrainToSelf() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            q.drainTo(q);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * drainTo(c) of empty queue doesn't transfer elements
     */
    public void testDrainTo() {
        SynchronousQueue q = new SynchronousQueue();
        ArrayList l = new ArrayList();
        q.drainTo(l);
        assertEquals(q.size(), 0);
        assertEquals(l.size(), 0);
    }

    /**
     * drainTo empties queue, unblocking a waiting put.
     */
    public void testDrainToWithActivePut() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue();
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                q.put(new Integer(1));
            }});

        t.start();
        ArrayList l = new ArrayList();
        Thread.sleep(SHORT_DELAY_MS);
        q.drainTo(l);
        assertTrue(l.size() <= 1);
        if (l.size() > 0)
            assertEquals(l.get(0), new Integer(1));
        t.join();
        assertTrue(l.size() <= 1);
    }

    /**
     * drainTo(null, n) throws NPE
     */
    public void testDrainToNullN() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            q.drainTo(null, 0);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * drainTo(this, n) throws IAE
     */
    public void testDrainToSelfN() {
        SynchronousQueue q = new SynchronousQueue();
        try {
            q.drainTo(q, 0);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * drainTo(c, n) empties up to n elements of queue into c
     */
    public void testDrainToN() throws InterruptedException {
        final SynchronousQueue q = new SynchronousQueue();
        Thread t1 = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                q.put(one);
            }});

        Thread t2 = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                q.put(two);
            }});

        t1.start();
        t2.start();
        ArrayList l = new ArrayList();
        Thread.sleep(SHORT_DELAY_MS);
        q.drainTo(l, 1);
        assertEquals(1, l.size());
        q.drainTo(l, 1);
        assertEquals(2, l.size());
        assertTrue(l.contains(one));
        assertTrue(l.contains(two));
        t1.join();
        t2.join();
    }

}
Revision:	1.26
Committed:	Sat Oct 9 19:30:35 2010 UTC (13 years, 7 months ago) by jsr166
Branch:	MAIN
Changes since 1.25:	+2 -2 lines
Log Message:	whitespace
#	Content
1	/*
2	* Written by Doug Lea with assistance from members of JCP JSR-166
3	* Expert Group and released to the public domain, as explained at
4	* http://creativecommons.org/licenses/publicdomain
5	* Other contributors include Andrew Wright, Jeffrey Hayes,
6	* Pat Fisher, Mike Judd.
7	*/
8
9	import junit.framework.*;
10	import java.util.*;
11	import java.util.concurrent.*;
12	import static java.util.concurrent.TimeUnit.MILLISECONDS;
13	import java.io.*;
14
15	public class SynchronousQueueTest extends JSR166TestCase {
16
17	public static class Fair extends BlockingQueueTest {
18	protected BlockingQueue emptyCollection() {
19	return new SynchronousQueue(true);
20	}
21	}
22
23	public static class NonFair extends BlockingQueueTest {
24	protected BlockingQueue emptyCollection() {
25	return new SynchronousQueue(false);
26	}
27	}
28
29	public static void main(String[] args) {
30	junit.textui.TestRunner.run(suite());
31	}
32
33	public static Test suite() {
34	return newTestSuite(SynchronousQueueTest.class,
35	new Fair().testSuite(),
36	new NonFair().testSuite());
37	}
38
39	/**
40	* A SynchronousQueue is both empty and full
41	*/
42	public void testEmptyFull() {
43	SynchronousQueue q = new SynchronousQueue();
44	assertTrue(q.isEmpty());
45	assertEquals(0, q.size());
46	assertEquals(0, q.remainingCapacity());
47	assertFalse(q.offer(zero));
48	}
49
50	/**
51	* A fair SynchronousQueue is both empty and full
52	*/
53	public void testFairEmptyFull() {
54	SynchronousQueue q = new SynchronousQueue(true);
55	assertTrue(q.isEmpty());
56	assertEquals(0, q.size());
57	assertEquals(0, q.remainingCapacity());
58	assertFalse(q.offer(zero));
59	}
60
61	/**
62	* offer(null) throws NPE
63	*/
64	public void testOfferNull() {
65	try {
66	SynchronousQueue q = new SynchronousQueue();
67	q.offer(null);
68	shouldThrow();
69	} catch (NullPointerException success) {}
70	}
71
72	/**
73	* add(null) throws NPE
74	*/
75	public void testAddNull() {
76	try {
77	SynchronousQueue q = new SynchronousQueue();
78	q.add(null);
79	shouldThrow();
80	} catch (NullPointerException success) {}
81	}
82
83	/**
84	* offer fails if no active taker
85	*/
86	public void testOffer() {
87	SynchronousQueue q = new SynchronousQueue();
88	assertFalse(q.offer(one));
89	}
90
91	/**
92	* add throws ISE if no active taker
93	*/
94	public void testAdd() {
95	try {
96	SynchronousQueue q = new SynchronousQueue();
97	assertEquals(0, q.remainingCapacity());
98	q.add(one);
99	shouldThrow();
100	} catch (IllegalStateException success) {}
101	}
102
103	/**
104	* addAll(null) throws NPE
105	*/
106	public void testAddAll1() {
107	try {
108	SynchronousQueue q = new SynchronousQueue();
109	q.addAll(null);
110	shouldThrow();
111	} catch (NullPointerException success) {}
112	}
113
114	/**
115	* addAll(this) throws IAE
116	*/
117	public void testAddAllSelf() {
118	try {
119	SynchronousQueue q = new SynchronousQueue();
120	q.addAll(q);
121	shouldThrow();
122	} catch (IllegalArgumentException success) {}
123	}
124
125	/**
126	* addAll of a collection with null elements throws NPE
127	*/
128	public void testAddAll2() {
129	try {
130	SynchronousQueue q = new SynchronousQueue();
131	Integer[] ints = new Integer[1];
132	q.addAll(Arrays.asList(ints));
133	shouldThrow();
134	} catch (NullPointerException success) {}
135	}
136
137	/**
138	* addAll throws ISE if no active taker
139	*/
140	public void testAddAll4() {
141	try {
142	SynchronousQueue q = new SynchronousQueue();
143	Integer[] ints = new Integer[1];
144	for (int i = 0; i < 1; ++i)
145	ints[i] = new Integer(i);
146	q.addAll(Arrays.asList(ints));
147	shouldThrow();
148	} catch (IllegalStateException success) {}
149	}
150
151	/**
152	* put(null) throws NPE
153	*/
154	public void testPutNull() throws InterruptedException {
155	try {
156	SynchronousQueue q = new SynchronousQueue();
157	q.put(null);
158	shouldThrow();
159	} catch (NullPointerException success) {}
160	}
161
162	/**
163	* put blocks interruptibly if no active taker
164	*/
165	public void testBlockingPut() throws InterruptedException {
166	Thread t = new Thread(new CheckedInterruptedRunnable() {
167	public void realRun() throws InterruptedException {
168	SynchronousQueue q = new SynchronousQueue();
169	q.put(zero);
170	}});
171
172	t.start();
173	Thread.sleep(SHORT_DELAY_MS);
174	t.interrupt();
175	t.join();
176	}
177
178	/**
179	* put blocks waiting for take
180	*/
181	public void testPutWithTake() throws InterruptedException {
182	final SynchronousQueue q = new SynchronousQueue();
183	Thread t = new Thread(new CheckedRunnable() {
184	public void realRun() throws InterruptedException {
185	int added = 0;
186	try {
187	while (true) {
188	q.put(added);
189	++added;
190	}
191	} catch (InterruptedException success) {
192	assertEquals(1, added);
193	}
194	}});
195
196	t.start();
197	Thread.sleep(SHORT_DELAY_MS);
198	assertEquals(0, q.take());
199	Thread.sleep(SHORT_DELAY_MS);
200	t.interrupt();
201	t.join();
202	}
203
204	/**
205	* timed offer times out if elements not taken
206	*/
207	public void testTimedOffer() throws InterruptedException {
208	final SynchronousQueue q = new SynchronousQueue();
209	Thread t = new Thread(new CheckedInterruptedRunnable() {
210	public void realRun() throws InterruptedException {
211	assertFalse(q.offer(new Object(), SHORT_DELAY_MS, MILLISECONDS));
212	q.offer(new Object(), LONG_DELAY_MS, MILLISECONDS);
213	}});
214
215	t.start();
216	Thread.sleep(SMALL_DELAY_MS);
217	t.interrupt();
218	t.join();
219	}
220
221
222	/**
223	* take blocks interruptibly when empty
224	*/
225	public void testTakeFromEmpty() throws InterruptedException {
226	final SynchronousQueue q = new SynchronousQueue();
227	Thread t = new Thread(new CheckedInterruptedRunnable() {
228	public void realRun() throws InterruptedException {
229	q.take();
230	}});
231
232	t.start();
233	Thread.sleep(SHORT_DELAY_MS);
234	t.interrupt();
235	t.join();
236	}
237
238
239	/**
240	* put blocks interruptibly if no active taker
241	*/
242	public void testFairBlockingPut() throws InterruptedException {
243	Thread t = new Thread(new CheckedInterruptedRunnable() {
244	public void realRun() throws InterruptedException {
245	SynchronousQueue q = new SynchronousQueue(true);
246	q.put(zero);
247	}});
248
249	t.start();
250	Thread.sleep(SHORT_DELAY_MS);
251	t.interrupt();
252	t.join();
253	}
254
255	/**
256	* put blocks waiting for take
257	*/
258	public void testFairPutWithTake() throws InterruptedException {
259	final SynchronousQueue q = new SynchronousQueue(true);
260	Thread t = new Thread(new CheckedRunnable() {
261	public void realRun() throws InterruptedException {
262	int added = 0;
263	try {
264	while (true) {
265	q.put(added);
266	++added;
267	}
268	} catch (InterruptedException success) {
269	assertEquals(1, added);
270	}
271	}});
272
273	t.start();
274	Thread.sleep(SHORT_DELAY_MS);
275	assertEquals(0, q.take());
276	Thread.sleep(SHORT_DELAY_MS);
277	t.interrupt();
278	t.join();
279	}
280
281	/**
282	* timed offer times out if elements not taken
283	*/
284	public void testFairTimedOffer() throws InterruptedException {
285	final SynchronousQueue q = new SynchronousQueue(true);
286	Thread t = new Thread(new CheckedInterruptedRunnable() {
287	public void realRun() throws InterruptedException {
288	assertFalse(q.offer(new Object(), SHORT_DELAY_MS, MILLISECONDS));
289	q.offer(new Object(), LONG_DELAY_MS, MILLISECONDS);
290	}});
291
292	t.start();
293	Thread.sleep(SMALL_DELAY_MS);
294	t.interrupt();
295	t.join();
296	}
297
298
299	/**
300	* take blocks interruptibly when empty
301	*/
302	public void testFairTakeFromEmpty() throws InterruptedException {
303	final SynchronousQueue q = new SynchronousQueue(true);
304	Thread t = new Thread(new CheckedInterruptedRunnable() {
305	public void realRun() throws InterruptedException {
306	q.take();
307	}});
308
309	t.start();
310	Thread.sleep(SHORT_DELAY_MS);
311	t.interrupt();
312	t.join();
313	}
314
315	/**
316	* poll fails unless active taker
317	*/
318	public void testPoll() {
319	SynchronousQueue q = new SynchronousQueue();
320	assertNull(q.poll());
321	}
322
323	/**
324	* timed pool with zero timeout times out if no active taker
325	*/
326	public void testTimedPoll0() throws InterruptedException {
327	SynchronousQueue q = new SynchronousQueue();
328	assertNull(q.poll(0, MILLISECONDS));
329	}
330
331	/**
332	* timed pool with nonzero timeout times out if no active taker
333	*/
334	public void testTimedPoll() throws InterruptedException {
335	SynchronousQueue q = new SynchronousQueue();
336	assertNull(q.poll(SHORT_DELAY_MS, MILLISECONDS));
337	}
338
339	/**
340	* Interrupted timed poll throws InterruptedException instead of
341	* returning timeout status
342	*/
343	public void testInterruptedTimedPoll() throws InterruptedException {
344	final SynchronousQueue q = new SynchronousQueue();
345	Thread t = new Thread(new CheckedInterruptedRunnable() {
346	public void realRun() throws InterruptedException {
347	q.poll(SMALL_DELAY_MS, MILLISECONDS);
348	}});
349
350	t.start();
351	Thread.sleep(SHORT_DELAY_MS);
352	t.interrupt();
353	t.join();
354	}
355
356	/**
357	* Interrupted timed poll throws InterruptedException instead of
358	* returning timeout status
359	*/
360	public void testFairInterruptedTimedPoll() throws InterruptedException {
361	Thread t = new Thread(new CheckedInterruptedRunnable() {
362	public void realRun() throws InterruptedException {
363	SynchronousQueue q = new SynchronousQueue(true);
364	q.poll(SMALL_DELAY_MS, MILLISECONDS);
365	}});
366
367	t.start();
368	Thread.sleep(SHORT_DELAY_MS);
369	t.interrupt();
370	t.join();
371	}
372
373	/**
374	* timed poll before a delayed offer fails; after offer succeeds;
375	* on interruption throws
376	*/
377	public void testFairTimedPollWithOffer() throws InterruptedException {
378	final SynchronousQueue q = new SynchronousQueue(true);
379	Thread t = new Thread(new CheckedRunnable() {
380	public void realRun() throws InterruptedException {
381	try {
382	assertNull(q.poll(SHORT_DELAY_MS, MILLISECONDS));
383	assertSame(zero, q.poll(LONG_DELAY_MS, MILLISECONDS));
384	q.poll(LONG_DELAY_MS, MILLISECONDS);
385	threadShouldThrow();
386	} catch (InterruptedException success) {}
387	}});
388
389	t.start();
390	Thread.sleep(SMALL_DELAY_MS);
391	assertTrue(q.offer(zero, SHORT_DELAY_MS, MILLISECONDS));
392	t.interrupt();
393	t.join();
394	}
395
396
397	/**
398	* peek returns null
399	*/
400	public void testPeek() {
401	SynchronousQueue q = new SynchronousQueue();
402	assertNull(q.peek());
403	}
404
405	/**
406	* element throws NSEE
407	*/
408	public void testElement() {
409	SynchronousQueue q = new SynchronousQueue();
410	try {
411	q.element();
412	shouldThrow();
413	} catch (NoSuchElementException success) {}
414	}
415
416	/**
417	* remove throws NSEE if no active taker
418	*/
419	public void testRemove() {
420	SynchronousQueue q = new SynchronousQueue();
421	try {
422	q.remove();
423	shouldThrow();
424	} catch (NoSuchElementException success) {}
425	}
426
427	/**
428	* remove(x) returns false
429	*/
430	public void testRemoveElement() {
431	SynchronousQueue q = new SynchronousQueue();
432	assertFalse(q.remove(zero));
433	assertTrue(q.isEmpty());
434	}
435
436	/**
437	* contains returns false
438	*/
439	public void testContains() {
440	SynchronousQueue q = new SynchronousQueue();
441	assertFalse(q.contains(zero));
442	}
443
444	/**
445	* clear ensures isEmpty
446	*/
447	public void testClear() {
448	SynchronousQueue q = new SynchronousQueue();
449	q.clear();
450	assertTrue(q.isEmpty());
451	}
452
453	/**
454	* containsAll returns false unless empty
455	*/
456	public void testContainsAll() {
457	SynchronousQueue q = new SynchronousQueue();
458	Integer[] empty = new Integer[0];
459	assertTrue(q.containsAll(Arrays.asList(empty)));
460	Integer[] ints = new Integer[1]; ints[0] = zero;
461	assertFalse(q.containsAll(Arrays.asList(ints)));
462	}
463
464	/**
465	* retainAll returns false
466	*/
467	public void testRetainAll() {
468	SynchronousQueue q = new SynchronousQueue();
469	Integer[] empty = new Integer[0];
470	assertFalse(q.retainAll(Arrays.asList(empty)));
471	Integer[] ints = new Integer[1]; ints[0] = zero;
472	assertFalse(q.retainAll(Arrays.asList(ints)));
473	}
474
475	/**
476	* removeAll returns false
477	*/
478	public void testRemoveAll() {
479	SynchronousQueue q = new SynchronousQueue();
480	Integer[] empty = new Integer[0];
481	assertFalse(q.removeAll(Arrays.asList(empty)));
482	Integer[] ints = new Integer[1]; ints[0] = zero;
483	assertFalse(q.containsAll(Arrays.asList(ints)));
484	}
485
486
487	/**
488	* toArray is empty
489	*/
490	public void testToArray() {
491	SynchronousQueue q = new SynchronousQueue();
492	Object[] o = q.toArray();
493	assertEquals(o.length, 0);
494	}
495
496	/**
497	* toArray(a) is nulled at position 0
498	*/
499	public void testToArray2() {
500	SynchronousQueue q = new SynchronousQueue();
501	Integer[] ints = new Integer[1];
502	assertNull(ints[0]);
503	}
504
505	/**
506	* toArray(null) throws NPE
507	*/
508	public void testToArray_BadArg() {
509	SynchronousQueue q = new SynchronousQueue();
510	try {
511	Object o[] = q.toArray(null);
512	shouldThrow();
513	} catch (NullPointerException success) {}
514	}
515
516
517	/**
518	* iterator does not traverse any elements
519	*/
520	public void testIterator() {
521	SynchronousQueue q = new SynchronousQueue();
522	Iterator it = q.iterator();
523	assertFalse(it.hasNext());
524	try {
525	Object x = it.next();
526	shouldThrow();
527	} catch (NoSuchElementException success) {}
528	}
529
530	/**
531	* iterator remove throws ISE
532	*/
533	public void testIteratorRemove() {
534	SynchronousQueue q = new SynchronousQueue();
535	Iterator it = q.iterator();
536	try {
537	it.remove();
538	shouldThrow();
539	} catch (IllegalStateException success) {}
540	}
541
542	/**
543	* toString returns a non-null string
544	*/
545	public void testToString() {
546	SynchronousQueue q = new SynchronousQueue();
547	String s = q.toString();
548	assertNotNull(s);
549	}
550
551
552	/**
553	* offer transfers elements across Executor tasks
554	*/
555	public void testOfferInExecutor() {
556	final SynchronousQueue q = new SynchronousQueue();
557	ExecutorService executor = Executors.newFixedThreadPool(2);
558
559	executor.execute(new CheckedRunnable() {
560	public void realRun() throws InterruptedException {
561	assertFalse(q.offer(one));
562	assertTrue(q.offer(one, MEDIUM_DELAY_MS, MILLISECONDS));
563	assertEquals(0, q.remainingCapacity());
564	}});
565
566	executor.execute(new CheckedRunnable() {
567	public void realRun() throws InterruptedException {
568	Thread.sleep(SMALL_DELAY_MS);
569	assertSame(one, q.take());
570	}});
571
572	joinPool(executor);
573	}
574
575	/**
576	* poll retrieves elements across Executor threads
577	*/
578	public void testPollInExecutor() {
579	final SynchronousQueue q = new SynchronousQueue();
580	ExecutorService executor = Executors.newFixedThreadPool(2);
581	executor.execute(new CheckedRunnable() {
582	public void realRun() throws InterruptedException {
583	assertNull(q.poll());
584	assertSame(one, q.poll(MEDIUM_DELAY_MS, MILLISECONDS));
585	assertTrue(q.isEmpty());
586	}});
587
588	executor.execute(new CheckedRunnable() {
589	public void realRun() throws InterruptedException {
590	Thread.sleep(SHORT_DELAY_MS);
591	q.put(one);
592	}});
593
594	joinPool(executor);
595	}
596
597	/**
598	* a deserialized serialized queue is usable
599	*/
600	public void testSerialization() throws Exception {
601	SynchronousQueue q = new SynchronousQueue();
602	ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
603	ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
604	out.writeObject(q);
605	out.close();
606
607	ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
608	ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
609	SynchronousQueue r = (SynchronousQueue)in.readObject();
610	assertEquals(q.size(), r.size());
611	while (!q.isEmpty())
612	assertEquals(q.remove(), r.remove());
613	}
614
615	/**
616	* drainTo(null) throws NPE
617	*/
618	public void testDrainToNull() {
619	SynchronousQueue q = new SynchronousQueue();
620	try {
621	q.drainTo(null);
622	shouldThrow();
623	} catch (NullPointerException success) {}
624	}
625
626	/**
627	* drainTo(this) throws IAE
628	*/
629	public void testDrainToSelf() {
630	SynchronousQueue q = new SynchronousQueue();
631	try {
632	q.drainTo(q);
633	shouldThrow();
634	} catch (IllegalArgumentException success) {}
635	}
636
637	/**
638	* drainTo(c) of empty queue doesn't transfer elements
639	*/
640	public void testDrainTo() {
641	SynchronousQueue q = new SynchronousQueue();
642	ArrayList l = new ArrayList();
643	q.drainTo(l);
644	assertEquals(q.size(), 0);
645	assertEquals(l.size(), 0);
646	}
647
648	/**
649	* drainTo empties queue, unblocking a waiting put.
650	*/
651	public void testDrainToWithActivePut() throws InterruptedException {
652	final SynchronousQueue q = new SynchronousQueue();
653	Thread t = new Thread(new CheckedRunnable() {
654	public void realRun() throws InterruptedException {
655	q.put(new Integer(1));
656	}});
657
658	t.start();
659	ArrayList l = new ArrayList();
660	Thread.sleep(SHORT_DELAY_MS);
661	q.drainTo(l);
662	assertTrue(l.size() <= 1);
663	if (l.size() > 0)
664	assertEquals(l.get(0), new Integer(1));
665	t.join();
666	assertTrue(l.size() <= 1);
667	}
668
669	/**
670	* drainTo(null, n) throws NPE
671	*/
672	public void testDrainToNullN() {
673	SynchronousQueue q = new SynchronousQueue();
674	try {
675	q.drainTo(null, 0);
676	shouldThrow();
677	} catch (NullPointerException success) {}
678	}
679
680	/**
681	* drainTo(this, n) throws IAE
682	*/
683	public void testDrainToSelfN() {
684	SynchronousQueue q = new SynchronousQueue();
685	try {
686	q.drainTo(q, 0);
687	shouldThrow();
688	} catch (IllegalArgumentException success) {}
689	}
690
691	/**
692	* drainTo(c, n) empties up to n elements of queue into c
693	*/
694	public void testDrainToN() throws InterruptedException {
695	final SynchronousQueue q = new SynchronousQueue();
696	Thread t1 = new Thread(new CheckedRunnable() {
697	public void realRun() throws InterruptedException {
698	q.put(one);
699	}});
700
701	Thread t2 = new Thread(new CheckedRunnable() {
702	public void realRun() throws InterruptedException {
703	q.put(two);
704	}});
705
706	t1.start();
707	t2.start();
708	ArrayList l = new ArrayList();
709	Thread.sleep(SHORT_DELAY_MS);
710	q.drainTo(l, 1);
711	assertEquals(1, l.size());
712	q.drainTo(l, 1);
713	assertEquals(2, l.size());
714	assertTrue(l.contains(one));
715	assertTrue(l.contains(two));
716	t1.join();
717	t2.join();
718	}
719
720	}